Injecting fuel into internal combustion engines



March 2 1935. i s, D. OLSEN 1,995,459

INJECTING FUEL INTO INTERNAL COMBUSTION ENGINES Filed July 26, 1932 {)NVEN TOR 15f 0. O4. Jf/V H TTORNEy Patented Mar. 26, 1935 Un ts!) STATES INJEC'IING FUEL INTO INTERNAL COMBUSTION ENGINES Simon Dokk Olsen, London, England Application July 26, 1932, Serial No. 624,796

In Great Britain July 31, 1931 10 Claims.

This invention relates to injecting fuel into internal combustion engines, and has for its main object to provide a new or improved apparatus for pumping and injecting fuel, and for obtaining an effective and efiicient admixture of the fuel with the air in the combustion space.

One characteristic of apparatus made in accordance with the invention lies in the fact that the compression pressure in the combustion space is utilized to compress the fuel oil in a reservoir ready for injection, and injection of the already compressed fuel starts upon the opening of a mechanically operated timing valve in the passage connecting the reservoir to the nozzle; another characteristic is that the pressure in the combustion space is utilized to impart a rotary movement to the nozzle; this rotary movement is thus variable with the load and can be arranged to be such as to give efficient combustion on heavy duty but sufiiciently less on light load to avoid any danger of detonation. The invention comprises these characteristics, as well as the new and improved features, combinations and arrangements embodied in the preferred form thereof which it is now proposed to describe by way of example in order that the nature of the invention may be clearly understood.

This form is illustrated by the accompanying drawing showing in sectional elevation the injection mechanism with the piston at the top of its stroke.

As illustrated fuel is supplied through the pipe 1 to a space including a small cylinder 2 immediately above a vertical plunger 3 which enters the cylinder 2 and compresses the fuel therein in a manner which will be hereinafter described.

The plunger 3 lower down in its length, is provided with ports 4 which communicate with a bore 5 in the plunger through which the fuel openings 7. The lower portion of this space is preferably fitted with a non-return valve 8 to prevent the cylinder pressure from being communicated to the bore in the plunger. Communicating with the ports 4 in the plunger 3 throughout the stroke of the latter is a passage 9 in which a timing valve 10 is incorporated; this passage 9 leads from the small cylinder 2 so that the fuel already compressed therein by the plunger 3 is injected whenever the timing valve 10 is opened. The timing valve 10 is of the spring-held balanced type, and may itself be provided with a relief passage 11 and valve 12, the latter valve being operated by a tappet 13, so

reaches a space 6 immediately above the nozzle.

as to close the relief passage 11 whenever the timing valve 10 is opened by the tappet 13.

The lower end of the plunger 3 is igyi acofinected to the nozzle 14 which wi ts associated parts including a sleeve 15 is slidable in a bore formed in-a fixed bush 16 in the cylinder head, and is of considerably greater area than that of the plunger 3. It will thus be apparentthat as the compression pressure increases the plunger 3 is forced upward to compress the fuel to an extent depending upon the compression pressure and that the movement of the nozzle depends upon the variation of the said pressure. It is preferred further to rotate the nozzle during the compression and injection period, and for this purpose a portion of the construction between the plunger and the nozzle may be threaded with one or more threads 19 of long pitch engaging a fixed nut 17 and so causinga consequent rotation with the up and down movement of the plunger.

The nozzle may be held in normal position by means of a spring 18 lying, for example, between this nut and an abutment 15a formed upon the sleeve 15 which slides in the bore '16 of the cylinder head and rigidly connects the actual nozzle portion to the lower part of the member incorporating the plunger 3. This sleeve 15 may have a flange 1517 at its upper end which enters a part lfibwherein it substantially fits at its lower position so as to provide a cushion as well as a stop at the lower extreme of the plunger stroke.

The operation of the apparatus is thus as follows:

The whole of the supply passages are filled by the pipe 1 with fuel coming from the tank or float chamber, and whenever the plunger 3 and nozzle 14 are in their lowest position the space 2 above the plunger becomes filled with fuel. As the piston rises to near the top of its stroke the nozzle and plunger are forced up with a rotary motion and fuel is compressed above the plunger 3. Upon operation of the timing valve 10, the space above the plunger is put into communication with the nozzle and injection starts; as ignition takes place and the pressure rises, the nozzle and plunger are forced upward with rotary motion, and the fuel injection takes place with corresponding increasing pressure during the period of injection until the mechanical valve 10 is permitted to close. The nozzle being preferably arranged with several very small apertures 7, '7 directed outwardly as well as downwardly thus makes a partial rotation and an upward movement during injection, and returns to its lowest position (shown in the drawing) under spring pressure as soon as the cylinderpressure is sufficiently low.

It will be appreciated that the injector mechamm for each individual cylinder including the fuel pump is thus readily incorporated in a selfcontalned unit, and that by varying the angle of advance of a cam 20 or like governing the timing valve the engine may be set for reverse running without further modification.

It is believed that the nozzle movement will give a more efllcient contact of the fuel with the com; pressed air in the compression space, and that the penetration will be more even owing to the increase of pressure behind the fuel as pressure rises in the combustion space. Clearly the nozzle might in certain cases be rotated during the upward movement of the plunger and its associated parts without itself actually moving upwardly, but the combined movement as described is preferred.

I claim:--

1. A fuel injection apparatus comprising a pressure cylinder formed with a fuel chamber, a pump plunger mounted for reciprocation in the cylinder and operative to create pressure on the fuel in the chamber, a nozzle carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, and cooperating means on the plunger and cylinder to compel rotary movement of the plunger and thereby of the nozzle in the reciprocation of the plunger.

2. A fuel injection apparatus comprising a pressure cylinder formed with a fuel chamber, a plunger mounted for reciprocation in the cylinder and operative to create pressure on the fuel in the chamber, a nozzle carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, and interengaging spirals of relatively large pitch formed on the plunger and cylinder to compel rotary movement of the plunger and thereby of the nozzle in the reciprocation of the plunger.

3. A fuel injection apparatus comprising a pressure cylinder formed with a fuel-receiving chamber, aplunger mounted for reciprocation in the cylinder and operative to create pressure on the fuel in said chamber, a nozzle carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, and a time-controlled valve for governing said .4. A fuel injection apparatus comprising a pressure cylinder formed with a fuel-receiving chamber, a plunger mounted for reciprocation in the cylinder and operative to create pressure on the fuel in said chamber, a nozzle carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle and a time-controlled valve for governing said passage, said passage in part passing through the plunger.

5. A construction as defined in claim 3, wherein the time-controlled valve is formed with a pressure relief passage and wherein the valve is operative to seal the passage against relief during movement of the valve to open the passage between the chamber and nozzle.

6. A fuel injection nozzle including a pressure cylinder formed with a fuel receiving chamber, a plunger mounted for reciprocation in the cylinder and operative in movement in one direction to create pressure on the fuel in the chamber,'said plunger depending below the cylinder, a nozzle carried by said depending portion of the plunger, a valve-controlled passage establishing communication between the chamber and" nozzle, and means for compelling rotary movement of the nozzle during reciprocations of the plunger.

7. A fuel injection nozzle including a pressure cylinder formed with a'fuel receiving chamber, a supply passage leading to the chamber, a plunger mounted for reciprocation in the cylinder and operative under an external predetermined pressure to create pressure on the fuel in the chamber, a nozzle removably carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, said passage being formed in part in the cylinder and in part in the plunger, and cooperating means on the plunger and cylinder to compel rotative movement of the plunger and thereby of the nozzle in the reciprocations of the plunger.

8. A fuel injection nozzle including a pressure cylinder formed with a fuel receiving chamber, a supply passage leading to the chamber, a plunger mounted for reciprocation in the cylinder and operative under an external predetermined pressure to create pressure on the fuel in the chamber, a nozzle removably carried by and movablewith the plunger, a passage establishing communication between the chamber and nozzle, said passage being formed in part in the cylinder and in part in the plunger, cooperating means on the plunger and cylinder to compel rotative movement of the plunger and thereby of the nozzle in the reciprocations of the plunger, and a timed valve controlling that part of the passage in the cylinder.

9. A fuel injection nozzle including a pressure cylinder formed with a fuel receiving chamber, a supply passage leading to the chamber, a plunger mounted for reciprocation in the cylinder and operative under an external predetermined pressure to create pressure on the fuel in the chamber, a nozzle removably carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, said passage being formed in part in the cylinder and in part in the plunger, cooperating means on the plunger and cylinder to compel rotative movement of the plunger and thereby of the nozzle in the reciprocations of the plunger, and a timed valve controlling that part of the passage in the cylinder, said valve formed with a relief passage open to the passage in the cylinder.

10. A fuel injection nozzle including a pressure cylinder formed with a fuel receiving chamber, a supply passage leading to the chamber, a plunger mounted for reciprocation in the cylinder and operative under an external predetermined pressure to create pressure on the fuel in the chamber, a nozzle removably carried by and movable with the plunger, a passage establishing communication between the chamber and nozzle, said passage being formed in part in the cylinder and in part in the plunger, cooperating means on the plunger and cylinder to compel rotative movement of the plunger and thereby of the nozzle in the reciprocations of the plunger, a timed valve controlling that part of the passage in the cylinder, said valve formed with a relief passage open to the passage in the cylinder, and a valve for controlling said passage, said latter valve being closed when the timed valve is opened and opened by excess pressure in the relief passage of the timed valve when said timed valve is closed.

SIMON DOKK OLSEN. 

